1. Field
An aspect of the present invention relates generally to a rechargeable battery.
2. Description of the Related Art
A rechargeable battery differs from a primary battery in that it can be repeatedly recharged and discharged, while a primary battery is incapable of being recharged.
Low-capacity rechargeable batteries are often used in small portable electronic devices such as mobile phones, notebook computers, and camcorders, while high-capacity rechargeable batteries are widely used as a power source for larger electric devices, such as driving a motor of a hybrid vehicle, etc. Recently, high power rechargeable batteries using a non-aqueous electrolyte and having high energy density have been developed, and these high power rechargeable batteries are formed by coupling a plurality of rechargeable batteries in series for use as a power source for driving a motor of a device requiring a large amount of electric power, for example, an electric vehicle, etc. High-capacity rechargeable battery modules normally include a plurality of rechargeable batteries connected in series, where each of these rechargeable batteries may be a cylindrical or prismatic shape.
In situations where foreign conductive materials such as nails, metal tools like awls, or other similar conductive materials enter a rechargeable battery cell, a short circuit may occur inside the rechargeable battery as a result. When the short circuit occurs, the internal temperature of the rechargeable battery may be abruptly increased resulting in an increased risk of ignition or explosion of the rechargeable battery. This risk that a high-capacity rechargeable battery may ignite or explode is even further increased when the current flow is large due to an external short circuit.